/* $Id: getopt_long.c,v 1.1 2003/02/16 17:17:31 neis Exp $ */
/*	$OpenBSD: getopt_long.c,v 1.11 2002/12/10 17:51:42 millert Exp $	*/
/*	$NetBSD: getopt_long.c,v 1.15 2002/01/31 22:43:40 tv Exp $	*/

/*
*
*  @file: option parser for any platform
*  @author: Michael Moore  moore!vicfast.com
*  @brief: parser any string to argc/argv list, most likly main calling
*  @date: 20111201
*  @version: 1.0
*
 */

#include <err.h>
#include <errno.h>
#include <getopt.h>
#include <stdlib.h>
#include <string.h>
#include "opt_arg.h"

#ifdef REPLACE_GETOPT
int opterr = 1;			/* if error message should be printed */
int optind = 1;			/* index into parent argv vector */
int optopt = '?';		/* character checked for validity */
char *optarg = NULL;		/* argument associated with option */
#endif
int optreset = 0;		/* reset getopt */

#define PRINT_ERROR	((opterr) && (*options != ':'))

#define FLAG_PERMUTE	0x01	/* permute non-options to the end of argv */
#define FLAG_ALLARGS	0x02	/* treat non-options as args to option "-1" */
#define FLAG_LONGONLY	0x04	/* operate as getopt_long_only */

/* return values */
#define	BADCH		(int)'?'
#define	BADARG		((*options == ':') ? (int)':' : (int)'?')
#define	INORDER 	(int)1

#define	EMSG		""

static int getopt_internal (int, char *const *, const char *,
			    const struct option *, int *, int);
static int parse_long_options (char *const *, const char *,
			       const struct option *, int *, int);
static int gcd (int, int);
static void permute_args (int, int, int, char *const *);

static char *place = EMSG;	/* option letter processing */

/* XXX: set optreset to 1 rather than these two */
static int nonopt_start = -1;	/* first non option argument (for permute) */
static int nonopt_end = -1;	/* first option after non options (for permute) */

/* Error messages */
static const char recargchar[] = "option requires an argument -- %c";
static const char recargstring[] = "option requires an argument -- %s";
static const char ambig[] = "ambiguous option -- %.*s";
static const char noarg[] = "option doesn't take an argument -- %.*s";
static const char illoptchar[] = "unknown option -- %c";
static const char illoptstring[] = "unknown option -- %s";

/*
 * Compute the greatest common divisor of a and b.
 */
static int
gcd (int a, int b)
{
  int c;

  c = a % b;
  while (c != 0) {
    a = b;
    b = c;
    c = a % b;
  }

  return (b);
}

/*
 * Exchange the block from nonopt_start to nonopt_end with the block
 * from nonopt_end to opt_end (keeping the same order of arguments
 * in each block).
 */
static void
permute_args (int panonopt_start, int panonopt_end, int opt_end,
	      char *const *nargv)
{
  int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
  char *swap;

  /*
   * compute lengths of blocks and number and size of cycles
   */
  nnonopts = panonopt_end - panonopt_start;
  nopts = opt_end - panonopt_end;
  ncycle = gcd (nnonopts, nopts);
  cyclelen = (opt_end - panonopt_start) / ncycle;

  for (i = 0; i < ncycle; i++) {
    cstart = panonopt_end + i;
    pos = cstart;
    for (j = 0; j < cyclelen; j++) {
      if (pos >= panonopt_end)
	pos -= nnonopts;
      else
	pos += nopts;
      swap = nargv[pos];
      /* LINTED const cast */
      ((char **) nargv)[pos] = nargv[cstart];
      /* LINTED const cast */
      ((char **) nargv)[cstart] = swap;
    }
  }
}

/*
 * parse_long_options --
 *	Parse long options in argc/argv argument vector.
 * Returns -1 if short_too is set and the option does not match long_options.
 */
static int
parse_long_options (char *const *nargv, const char *options,
		    const struct option *long_options, int *idx,
		    int short_too)
{
  char *current_argv, *has_equal;
  size_t current_argv_len;
  int i, match;

  current_argv = place;
  match = -1;

  optind++;

  if ((has_equal = strchr (current_argv, '=')) != NULL) {
    /* argument found (--option=arg) */
    current_argv_len = has_equal - current_argv;
    has_equal++;
  }
  else
    current_argv_len = strlen (current_argv);

  for (i = 0; long_options[i].name; i++) {
    /* find matching long option */
    if (strncmp (current_argv, long_options[i].name, current_argv_len))
      continue;

    if (strlen (long_options[i].name) == current_argv_len) {
      /* exact match */
      match = i;
      break;
    }
    /*
     * If this is a known short option, don't allow
     * a partial match of a single character.
     */
    if (short_too && current_argv_len == 1)
      continue;

    if (match == -1)		/* partial match */
      match = i;
    else {
      /* ambiguous abbreviation */
      if (PRINT_ERROR)
	warnx (ambig, (int) current_argv_len, current_argv);
      optopt = 0;
      return (BADCH);
    }
  }
  if (match != -1) {		/* option found */
    if (long_options[match].has_arg == no_argument && has_equal) {
      if (PRINT_ERROR)
	warnx (noarg, (int) current_argv_len, current_argv);
      /*
       * XXX: GNU sets optopt to val regardless of flag
       */
      if (long_options[match].flag == NULL)
	optopt = long_options[match].val;
      else
	optopt = 0;
      return (BADARG);
    }
    if (long_options[match].has_arg == required_argument ||
	long_options[match].has_arg == optional_argument) {
      if (has_equal)
	optarg = has_equal;
      else if (long_options[match].has_arg == required_argument) {
	/*
	 * optional argument doesn't use next nargv
	 */
	optarg = nargv[optind++];
      }
    }
    if ((long_options[match].has_arg == required_argument)
	&& (optarg == NULL)) {
      /*
       * Missing argument; leading ':' indicates no error
       * should be generated.
       */
      if (PRINT_ERROR)
	warnx (recargstring, current_argv);
      /*
       * XXX: GNU sets optopt to val regardless of flag
       */
      if (long_options[match].flag == NULL)
	optopt = long_options[match].val;
      else
	optopt = 0;
      --optind;
      return (BADARG);
    }
  }
  else {			/* unknown option */
    if (short_too) {
      --optind;
      return (-1);
    }
    if (PRINT_ERROR)
      warnx (illoptstring, current_argv);
    optopt = 0;
    return (BADCH);
  }
  if (idx)
    *idx = match;
  if (long_options[match].flag) {
    *long_options[match].flag = long_options[match].val;
    return (0);
  }
  else
    return (long_options[match].val);
}

/*
 * getopt_internal --
 *	Parse argc/argv argument vector.  Called by user level routines.
 */
static int
getopt_internal (int nargc, char *const *nargv, const char *options,
		 const struct option *long_options, int *idx, int flags)
{
  char *oli;			/* option letter list index */
  int optchar, short_too;
  static int posixly_correct = -1;

  if (options == NULL)
    return (-1);

  /*
   * Disable GNU extensions if POSIXLY_CORRECT is set or options
   * string begins with a '+'.
   */
  if (posixly_correct == -1)
    posixly_correct = (getenv ("POSIXLY_CORRECT") != NULL);
  if (posixly_correct || *options == '+')
    flags &= ~FLAG_PERMUTE;
  else if (*options == '-')
    flags |= FLAG_ALLARGS;
  if (*options == '+' || *options == '-')
    options++;

  /*
   * XXX Some GNU programs (like cvs) set optind to 0 instead of
   * XXX using optreset.  Work around this braindamage.
   */
  if (optind == 0)
    optind = optreset = 1;

  optarg = NULL;
  if (optreset)
    nonopt_start = nonopt_end = -1;
start:
  if (optreset || !*place) {	/* update scanning pointer */
    optreset = 0;
    if (optind >= nargc) {	/* end of argument vector */
      place = EMSG;
      if (nonopt_end != -1) {
	/* do permutation, if we have to */
	permute_args (nonopt_start, nonopt_end, optind, nargv);
	optind -= nonopt_end - nonopt_start;
      }
      else if (nonopt_start != -1) {
	/*
	 * If we skipped non-options, set optind
	 * to the first of them.
	 */
	optind = nonopt_start;
      }
      nonopt_start = nonopt_end = -1;
      return (-1);
    }
    if (*(place = nargv[optind]) != '-' ||
	(place[1] == '\0' && strchr (options, '-') == NULL)) {
      place = EMSG;		/* found non-option */
      if (flags & FLAG_ALLARGS) {
	/*
	 * GNU extension:
	 * return non-option as argument to option 1
	 */
	optarg = nargv[optind++];
	return (INORDER);
      }
      if (!(flags & FLAG_PERMUTE)) {
	/*
	 * If no permutation wanted, stop parsing
	 * at first non-option.
	 */
	return (-1);
      }
      /* do permutation */
      if (nonopt_start == -1)
	nonopt_start = optind;
      else if (nonopt_end != -1) {
	permute_args (nonopt_start, nonopt_end, optind, nargv);
	nonopt_start = optind - (nonopt_end - nonopt_start);
	nonopt_end = -1;
      }
      optind++;
      /* process next argument */
      goto start;
    }
    if (nonopt_start != -1 && nonopt_end == -1)
      nonopt_end = optind;

    /*
     * Check for "--" or "--foo" with no long options
     * but if place is simply "-" leave it unmolested.
     */
    if (place[1] != '\0' && *++place == '-' &&
	(place[1] == '\0' || long_options == NULL)) {
      optind++;
      place = EMSG;
      /*
       * We found an option (--), so if we skipped
       * non-options, we have to permute.
       */
      if (nonopt_end != -1) {
	permute_args (nonopt_start, nonopt_end, optind, nargv);
	optind -= nonopt_end - nonopt_start;
      }
      nonopt_start = nonopt_end = -1;
      return (-1);
    }
  }

  /*
   * Check long options if:
   *  1) we were passed some
   *  2) the arg is not just "-"
   *  3) either the arg starts with -- we are getopt_long_only()
   */
  if (long_options != NULL && place != nargv[optind] &&
      (*place == '-' || (flags & FLAG_LONGONLY))) {
    short_too = 0;
    if (*place == '-')
      place++;			/* --foo long option */
    else if (*place != ':' && strchr (options, *place) != NULL)
      short_too = 1;		/* could be short option too */

    optchar = parse_long_options (nargv, options, long_options,
				  idx, short_too);
    if (optchar != -1) {
      place = EMSG;
      return (optchar);
    }
  }

  if ((optchar = (int) *place++) == (int) ':' ||
      (oli = strchr (options, optchar)) == NULL) {
    /*
     * If the user didn't specify '-' as an option,
     * assume it means -1 as POSIX specifies.
     */
    if (optchar == (int) '-')
      return (-1);
    /* option letter unknown or ':' */
    if (!*place)
      ++optind;
    if (PRINT_ERROR)
      warnx (illoptchar, optchar);
    optopt = optchar;
    return (BADCH);
  }
  if (long_options != NULL && optchar == 'W' && oli[1] == ';') {
    /* -W long-option */
    if (*place)
      /* no space */
      /* NOTHING */
      ;
    else if (++optind >= nargc) {	/* no arg */
      place = EMSG;
      if (PRINT_ERROR)
	warnx (recargchar, optchar);
      optopt = optchar;
      return (BADARG);
    }
    else			/* white space */
      place = nargv[optind];
    optchar = parse_long_options (nargv, options, long_options, idx, 0);
    place = EMSG;
    return (optchar);
  }
  if (*++oli != ':') {		/* doesn't take argument */
    if (!*place)
      ++optind;
  }
  else {			/* takes (optional) argument */
    optarg = NULL;
    if (*place)			/* no white space */
      optarg = place;
    /* XXX: disable test for :: if PC? (GNU doesn't) */
    else if (oli[1] != ':') {	/* arg not optional */
      if (++optind >= nargc) {	/* no arg */
	place = EMSG;
	if (PRINT_ERROR)
	  warnx (recargchar, optchar);
	optopt = optchar;
	return (BADARG);
      }
      else
	optarg = nargv[optind];
    }
    place = EMSG;
    ++optind;
  }
  /* dump back option letter */
  return (optchar);
}

#ifdef REPLACE_GETOPT
/*
 * getopt --
 *	Parse argc/argv argument vector.
 *
 * [eventually this will replace the BSD getopt]
 */
int
getopt (int nargc, char *const *nargv, const char *options)
{

  /*
   * We dont' pass FLAG_PERMUTE to getopt_internal() since
   * the BSD getopt(3) (unlike GNU) has never done this.
   *
   * Furthermore, since many privileged programs call getopt()
   * before dropping privileges it makes sense to keep things
   * as simple (and bug-free) as possible.
   */
  return (getopt_internal (nargc, nargv, options, NULL, NULL, 0));
}
#endif /* REPLACE_GETOPT */

/*
 * getopt_long --
 *	Parse argc/argv argument vector.
 */
int
mgetopt_long (nargc, nargv, options, long_options, idx)
     int nargc;
     char *const *nargv;
     const char *options;
     const struct option *long_options;
     int *idx;
{

  return (getopt_internal (nargc, nargv, options, long_options, idx,
			   FLAG_PERMUTE));
}

/*
 * getopt_long_only --
 *	Parse argc/argv argument vector.
 */
int
mgetopt_long_only (nargc, nargv, options, long_options, idx)
     int nargc;
     char *const *nargv;
     const char *options;
     const struct option *long_options;
     int *idx;
{

  return (getopt_internal (nargc, nargv, options, long_options, idx,
			   FLAG_PERMUTE | FLAG_LONGONLY));
}


inline char *
findspace (char *src)
{
  register char *t1;
  register char *t2;

  t1 = strchr (src, ' ');
  t2 = strchr (src, '\t');
  if (t1 && t2) {
    if (t1 < t2)
      t2 = NULL;
    else
      t1 = NULL;
  }

  if (t1)
    return t1;
  return t2;
}

int
argcount (const char *string)
{
  int ln;
  int cnt;
  int i;

  cnt = 1;
  ln = strlen (string);
  i = 0;

  while (i < ln) {
    if (isspace (string[i])) {
      while (isspace (string[i]))
	++i;
      if (string[i])
	++cnt;
    }
    ++i;
  }

  return cnt;
}

optionArgList *
new_args (void)
{
  optionArgList *res;

  res = (optionArgList *) malloc (sizeof (optionArgList));
  res->argc = 0;
  res->argv = NULL;
  return (res);
}

void
add_args (optionArgList * arg, const char *elm)
{
  if (arg->argc) {
    arg->argv =
      (char **) realloc (arg->argv, (arg->argc + 1) * sizeof (char *));
    arg->argv[arg->argc++] = strdup (elm);
  }
  else {
    arg->argc = 1;
    arg->argv = (char **) malloc (sizeof (char *));
    arg->argv[0] = strdup (elm);
  }
}

optionArgList *
make_args (const char *string)
{
  optionArgList *result;
  char *rightbound;
  char *word;
  char *crsr;
  int count;
  int pos;

  result = (optionArgList *) malloc (sizeof (optionArgList));
  count = argcount (string);
  result->argc = count;
  result->argv = (char **) malloc (count * sizeof (char *));

  crsr = (char *) string;
  pos = 0;

  while ((rightbound = findspace (crsr))) {
    word = (char *) malloc ((rightbound - crsr + 3) * sizeof (char));
    memcpy (word, crsr, rightbound - crsr);
    word[rightbound - crsr] = 0;
    result->argv[pos++] = word;
    crsr = rightbound;
    while (isspace (*crsr))
      ++crsr;
  }
  if (*crsr) {
    word = strdup (crsr);
    result->argv[pos++] = word;
  }

  return result;
}

void
destroy_args (optionArgList * lst)
{
  int i;
  for (i = 0; i < lst->argc; ++i)
    free (lst->argv[i]);
  free (lst->argv);
  free (lst);
}
